In recent years, as a countermeasure to the depletion of the earth's oil resources, and global warming, the improvement of fuel consumption has become of great importance to the automobile industry in particular, at the same time, various sound absorbing materials has been provided for the sound proofing of the interiors/exteriors of automobiles, in an effort to reduce noise. As said sound absorbing material, a molded laminated material obtained by molding a laminated material, consisting of a sound absorbing base material and a surface material laminated thereon and into a prescribed shape, has generally been used.
As common material used in said sound absorbing material, a porous material, for instance, a fiber sheet such as nonwoven fabric, a porous material such as glass wool, foamed polyurethane or the like has been used. Further, to maximize the sound absorbing and insulating performance of the final product for various frequencies, it has been known that the airflow resistance should be adjusted to be in the range of between about 0.6 and 20.0 kPa·s/m.
For instance, Patent Literature 1 discloses a sound absorbing felt made of a single layered felt. Further, Patent Literature 2 discloses an automotive interior finishing material consisting of a fiber web to which a synthetic resin binder is attached. Further, Patent Literature 3 discloses an automotive insulation material consisting of a laminated material of a sound absorbing material made from a fiber aggregate and a surface material made from a foamed material.    Patent Literature 1; Tokkai 2005-195989    Patent Literature 2; Tokkai 2004-325973    Patent Literature 3; Tokkai 2003-081028